Characteristic base lesion profiles from hydroxyl-radical induced oxidative damage occur in DNA from normal breast tissue compared to DNA from invasive ductal carcinomas or histologically normal breast tissue from breast cancer patients. These profiles shift from predominantly non- mutagenic lesions in non-cancer tissues to mutagenic lesions in cancer tissues, regulated, most probably, the cellular redox potential. Evidence indicates the nature of DNA base lesions may be predictive of future breast cancer risk. These lesions are quantifiable using gas- chromatography-mass spectrometry or HPLC analyses on isolated and derivatized DNAs. The objective is to develop DNA base lesion-specific monoclonal antibodies to establish a quantitative immunoassay. Such an assay would provide a reliable quantitation method using low-cost technology with critical importance in future clinical applications. Base lesion haptens will be prepared and linked to carrier protein for immunization in mice. Hybridomas will be screened for lesion specificity, binding affinity, and linear antigen binding response. Initial characterization of antibodies will involve analysis of hapten conjugated proteins and physiological DNA specimens of known base lesion concentration as determined by standard gas-chromatography-mass spectrometric determinations. Based upon these results, antibodies will be selected for their suitability in further development of immunoassays. PROPOSED COMMERCIAL APPLICATION: A quantitative immunoassay for hydroxyl- radical induced DNA base lesions would have commercial application in a diagnostic test defining genotoxic injury present in a tissue. This technology has application in human health (e.g., breast cancer risk assessment) and in environmental impact and remediation monitoring of hazardous sites.